1. Field of the Invention
The invention relates to a sliding device, and particularly to a sliding device configured in a portable electrical apparatus capable of allowing a sub-housing of the portable electrical apparatus sliding on a main housing of the portable electrical apparatus.
2. The Related Art
According to the current development of communication technology, portable electrical apparatuses such as mobile phones and personal digital assistants etc, are capable of providing wireless communication. One kind of portable electrical apparatuses is a sliding-type portable electrical apparatus. The sliding-type portable apparatus has a sliding device configured therein capable of allowing a sub-housing sliding on a main housing of the portable electrical apparatus. In consideration of carrying and downsizing issues, the sub-housing slides above the main housing to an open position for using. Otherwise, the sub-housing slides to cover the main housing of the portable electrical apparatus to a close position for an idle or standby situation.
A detailed sliding device adapted for portable electrical apparatuses is disclosed in United States Patent Application Publication No. 2006/0068859 (herein incorporated by reference in its entirety). It shows the sliding device includes a first housing, a second housing and a driving unit. The driving unit includes a motor and a gear box connected to the motor. A slide cam is connected to the gear box and an elastic member is contained in the slide cam. A guide cam is contained the slide cam and the elastic member, and connected the gear box. A housing receives the motor, the gear box, the slide cam, the elastic member and the guide cam. A pinion is connected to the guide cam.
A first hinge coupled to the first housing has a rack gear meshed with the pinion and a travel-enlarging member connected to the rack gear. A second hinge coupled to the second housing has a contact member protruded therefrom to contact the travel-enlarging member. Rotation of the pinion in response to the driving force of the driving unit is converted into a linear movement of the rack gear, and a distance of the linear movement of the rack gear is enlarged by means of the travel-enlarging member, so that the second housing coupled to the second hinge is slid on the first housing coupled to the first hinge.
However, the above described structure of the sliding device is much complicated to deploy because the operation must cooperate the first hinge, the second hinge and the driving unit all together. Furthermore, the volume of the mechanism is large because of the utilized motor.